Hi. I have a VW OEM towbar (VGA 803 921 G504 ) for my Mk5 Golf.

What is the torque nm to fasten this towbar please? It uses M12 hex bolts, but I'm not after torque specs for M12 8.8 hex bolts (which can run very high). Bolt length I have 40mm and 25mm to choose from. 25mm bolts reach...